1. Field of the Invention
The present invention relates to a wrist support with a computer input device in the form of a unitary member for ergonomically correct keyboard operation and control of position of a cursor or object on computer monitors.
2. Description of the Related Art
Conventional computer working spaces include a keyboard, a computer together with a computer monitor, and a supplemental input device as a separate member. Lately, employment of wrist supports in the form of elongated and compact bodies with a height corresponding to the height of the keyboard have been recommended to avoid physical damages to the wrist during frequent or long-term use of the keyboard. Such a wrist support is adapted to be positioned in front of the keyboard.
The most conventional input device to use for control of cursor movement on the monitor is the so-called "mouse" or track ball device. The primary function of the mouse is to move the cursor or a pointing marker. Conventional mice are, furthermore, provided with functions keys to select functions the marker points on.
The known mouse design operates on various different principles. Common to all the principles is that physical movement of the mouse body controls the movement of a cursor or marker on the computer screen. During the movement of the mouse, rotational movement of a roller ball arranged within the housing of the mouse is converted by means of electronic motion sensors to digital signals. These signals are forwarded to a microprocessor, which interprets the digital values to represent the movement of the mouse. The digital information from the sensors is converted into an appropriate data format and sent to the computer. In the computer, the data is converted via a software program to the rendering of an object or to a two-dimensional movement of the cursor or marker on the monitor.
Input devices of the above-described kind are available in a number of designs with a variety of different electronic sensors for providing proper and effective translation of physical movement of the mouse device into digital signals for cursor control.
The main drawback of the known mouse design is, however, that it places a serious strain (and risk of injury) to the wrist and hand moving the mouse if used for longer periods of time.
In the past, attempts have been made to provide input devices without the above drawbacks of the known mouse designs. These prior art devices control in general data input by means of stationary sensors, such as piezoelectrical or strain gauge transducers. A strain gauge utilizes the change of electrical resistance to measure strain. The resistance of a strain gauge is the electrical resistance between two metal strips designed for connection of a measuring cable or between solder taps. The transducers are bonded to a stationary control stick and measure stress when the stick is deflected during actuation. The stick is usually arranged uprightly on a reference plate.
A stationary input device of the above kind is disclosed in Great Britain Patent Application No. 2,287,526. The disclosed device includes a flat plate on which a control stick is arranged vertically. On the stick, strain gauges are adhered to four side faces of the stick, so that deflection of the stick in the X or Y direction is detected by strain gauges adhered to the corresponding side face of the stick. The input device is integrated into the keyboard and typically located a central position between the keys.